A South Korean soldier aims his gun at the checkpoint in Paju, north of Seoul, near the demilitarised zone. (AP)

Seoul, Oct. 7 (Reuters): South Korean troops fired warning shots today after five North Korean soldiers briefly crossed into the southern side of the demilitarised zone (DMZ) dividing the two, South Korea’s joint chiefs of staff said.

The skirmish comes amid rising tension on the peninsula after Pyongyang said on Tuesday it planned to conduct a nuclear test.

“Our troops fired warning shots at the five North Korean soldiers after they climbed over the military demarcation line despite several loudspeaker warnings,” the military command said. It said they went about 30 metres across the line at around 0415 GMT and returned after the shots were fired.

An officer at the Joint Chiefs office said that the South had fired about 60 rounds. He said that only one of the five North Koreans was armed, the soldier did not fire back and no injuries were reported. “We don’t know what their intentions were,” the officer said.

In late May, two North Koreans crossed the military line but also retreated after South Korean guards fired warning shots.

The two Koreas remain technically at war, more than half a century after the inconclusive truce which halted the 1950-53 Korean conflict.

UN envoy

North Korea’s deputy ambassador to the UN will be transferred back to North Korea and his post may not be refilled, the Japanese daily Mainichi Shimbun reported from Tokyo today.